Ebullient cooling system for automotive gasoline engines with constant temperature passenger space heater



y 968 L. P. BARLOW 3,384,304

EBULLIENT COOLING SYSTEM FOR AUTOMOTIVE GASOLINE ENGINES WITH CONSTANT TEMPERATURE PASSENGER SPACE HEATER Filed April 5, 1967 5 Sheets-Sheet 1 INVENTOR.

LESTER P. BARLOW BY J A TTORNEYS.

May 21, 1968 L. P. BARLOW 3,384,304

EBULLIENT COOLING SYSTEM FOR AUTOMOTIVE GASOLINE ENGINES WITH CONSTANT TEMPERATURE PASSENGER SPACE HEATER Filed April 3, 1967 a Sheets-Sheet 2 III-E02 CONDENSER I N VEN'TOR.

LESTER P. BARLOW ATTORNEYS.

May 21, 1968 L. P. BARLOW 3,384,304

EBULLIENT COOLING SYSTEM FOR AUTOMOTIVE GASOLINE ENGINES WITH CONSTANT TEMPERATURE PASSENGER SPACE HEATER Filed April 3, 1967 5 Sheets-Sheet 5 TO ENGINE COOLANT' PUMP ll FROM ENGINE JACKET OUTLEZE JAPOR AND m3 RTE-541 INVENTOR.

LESTER P. BARLOW ATTORNEYS.

May 21, 1968 L. P. BARLOW 3,384,304

EBULLIENT COOLING SYSTEM FOR AUTOMOTIVE GASOLINE ENGINES WITH CONSTANT TEMPERATURE PASSENGER SPACE HEATER Filed April 5, 1967 5 Sheets-Sheet 4 HEATED AIR IfmEm A/ TO COMPENSATOR JET STREAM 43 HEQZ IN VENTOR.

LESTER P. BARLOW A TTOEWEYS May 21, 1968 L. P. BARLOW 3,384,304

EBULLIENT COOLING SYSTEM FOR AUTOMOTIVE GASOLINE ENGINES WITH CONSTANT TEMPERATURE PASSENGER SPACE HEATER Filed April 3, 1967 5 Sheets-Sheet 5 HEEL: E

CON DENSATE N ID INVENTOR.

LESTER P. BARLOW A TTORNEYS.

United States Patent 3,384,304 EBULLIENT COOLING SYSTEM FOR AUTOMO- TIVE GASOLINE ENGINES WITH CONSTANT TEMPERATURE PASSENGER SPACE HEATER Lester P. Barlow, Stamford, Conn., assignor to The Barlow Vapor Cooling Company, Stamford, Conn., a corporation of Connecticut Continuation-in-part of application Ser. No. 568,684, July 28, 1966. This application Apr. 3, 1967, Ser. No. 627,945

6 Claims. (Cl. 237-8) ABSTRACT OF THE DISCLOSURE An ebullient cooling system for automotive gasoline engines circulates a mixture of coolant vapor and coolant liquid at its boiling temperature from the engine cooling jacket into a chamber in a passenger space heater. The vapor separates from the liquid in the heater chamber and this vapor passes into a condenser, while the liquid in the heater chamber is returned to the circulation path through the engine cooling jacket. In one embodiment the mixture of coolant vapor and coolant liquid at its boiling temperature enters another chamber for initial separation of liquid and vapor prior to entering the heater chamber. In another embodiment the mixture of coolant vapor and liquid passes from the jacket outlet through a conduit directly into the heater chamber. In both embodiments of the system the passenger heater itself remains at substantially constant temperature, namely the boiling temperature of the coolant, during operation of the engine over an extremely wide range of different conditions, and thus the passenger compartment is readily maintained at a uniform temperature without complex controls. The heater chamber provides the dual functions of the compensating chamber and the heater, thus conserving space beneath the hood.

Specification This application is a continuation-in-part of my application Ser. No. 568,684, filed July 28, 1966, now Patent No. 3,312,204. The present invention relates to an ebullient cooling system for automotive gasoline engines including a constant temperature passenger space heater having a chamber wherein coolant vapor is separated from coolant liquid at its boiling point.

The various features, aspects and advantages of this invention will become apparent from the following description of two illustrative embodiments thereof, considered in conjunction with the drawings which accompany and form part of the specification.

In the drawings:

FIGURE 1 is a side view of a high-compression automobile engine having an ebullient cooling system embodying the present invention;

FIGURE 2 is a top view of the engine;

FIGURE 3 is an enlarged front view of the compensating chamber, which is seen in FIGURES 1 and 2 positioned immediately behind the plane of revolution of the fan blades;

FIGURES 4 and 5 are side and top views of the compensating chamber of FIGURE 3;

FIGURE 6 is an enlarged elevational sectional view of the automobile heater, which is seen in FIGURES 1 and 2 to be positioned near the passenger compartment;

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FIGURE 7 is an illustration of a vacuum-controlled spring plug for preventing loss of coolant when the engine is shut off due to heat stored in the engine parts; and

FIGURE 8 is a side view of a high-compression automobile engine similar to FIGURE 1 and showing another ebullient cooling system embodying the present invention.

FIGURES l and 2 show a high-compression automobile engine 14 having a compression ratio exceeding 8.5 to 1 and including a conventional air intake and carburetor 8, and it includes a conventional ignition system, except that the timing of the ignition spark is set at a predetermined time to occur effectively at top dead center of the piston stroke in each cylinder. The hydrocarbon fuel being burned is devoid of anti-knock additives, such as lead tetraethyl. The fuel does not detonate (knock) during the compression stroke, and upon ignition by the spark .at the conclusion of the compression stroke, the fuel burns at a fast rate, whereby the mileage per gallon is increased and the released air contaminants are reduced.

The cooling system includes several novel features. As shown by the flow arrows 10 in FIGURE 1 the coolant liquid at its boiling temperature is pumped by a conventional coolant pump 11 into the cooling jacket 12 surrounding the cylinder walls of the high-compression engine 14. The coolant liquid absorbs heat from the engine and progressively greater volumes of vapor become mixed with the coolant flow to increase the velocity. The resulting high velocity mixture of vapor and liquid is passed up through an opening 15 in cylinder head gasket 17 and into the head jacket 18 so that there is an intense scrubbing of the coolant mixture against the interior surfaces of the head jacket as it flows forward at high speed as indicated by the arrows 19. In this engine there are also small orifices in the head gasket 17. These orifices are positioned near the location of the respective spark plug mountings for applying additional cooling action 16 to the spark plugs.

The high velocity flow 19 of the coolant, both liquid and vapor passes forward out through a jacket outlet 20 and through connection means 21 into the inlet 22 of a compensating chamber 24. This outlet 20 may be the same size as in a conventional engine, but I prefer to enlarge this outlet somewhat so as to allow the high velocity flow 19 to occur without any substantial back pressure. As seen in FIGURES 3, 4 and 5, this high velocity flow continues through a duct 25 within the compensating chamber which is curved to have its discharge end 26 aimed toward a bottom outlet port 27.

The coolant vapor 28 breaks away from the liquid after jetting out of the discharge nozzle 26, and this vapor goes to the upper part of the compensating chamber 24, where there is an outlet 30 for the wet vapor. The coolant liquid is driven by the jet stream 49 out through the bottom outlet port 27 having a connection 31 directly into the engine pump 11. This pump is a conventional automobile cooling pump. The coolant liquid being propelled from the compensating chamber 24 through the port 27 is at its boiling temperature and carries some entrained vapor back through the pump 11 into the jacket 12. The pressure with which the coolant liquid is driven through the connection means 31 into the pump 11 prevents the pump from becoming vapor bound.

The wet vapor from the compensating chamber 24 flows at high speed out of the upper outlet 30 and through tubing connection means 32 to an inlet 33 (FIG- URE 6) of a combination expansion tank and car heater unit 34. Within this unit 34 is a tank 35, and the wet vapor flows with force downward through a duct 36. Below the lower end of this duct 36 the liquid and vapor separate, with some of the liquid remaining in the bottom of the tank and some of the liquid being propelled down out of a return port 38 to be returned as hot liquid through tubing connection means 39 to a second inlet 40 (FIGURES 3, 4, and 5) into the compensating chamber 24.

The hot liquid passes through a second curved duct 41 within the compensating chamber having its discharge end 42 aimed toward the outlet 27 and positioned adjacent to the other nozzle 26 so that a stream 43 of hot liquid merges with the jet 49 in flowing out of the outlet port 27 toward the engine pump 11 and thus back into the jacket circulation path. It is noted that the outlet port 27 has a larger size than the discharge end 26 or 42 so that the jet streams 49 and 43 can readily entrain liquid coolant to be returned from the compensating chamber 24 to the engine jacket 12.

Within the tank 35 (FIGURE 6) dry vapor flows out of the top outlet 44 and down through tube connection means 45 to the bottom collector pan 46 of a vapor condenser 50.

Advantageously, the compensating chamber 24 plus the expansion tank 35 serve as two coolant liquid traps in cascaded relationship. They prevent any substantial amount of the hot liquid from reaching the condenser 50, and so they conserve heat energy (B.t.u.s), which helps in increasing engine efliciency by preventing Waste of heat energy. Thus, only substantially dry vapor reaches the multiple vertical cooling passages 51 of the condenser 50 extending up from the collector 46. As the vapor flows up these passages 51, it loses its heat of vaporization and moves only a relatively short distance before it becomes condensed and falls back down into the collector 46 as condensate liquid at just below its boiling point. The condenser passages 51 have associated external fins 52 of metal of good heat conductivity, such as copper or aluminum, for dissipating the heat of vaporization into the air stream passing through the condenser 50. The car is shown as including a conventional front grill 53 and a conventional low hood 54.

It will be appreciated that the condensate liquid is at a temperature only just slightly below its boiling point. From the collector pan 46 the hot condensate liquid flows down through a pipe 56 into a condensate pump 58. This pump 58 sends the liquid up through small diameter tubing 59 and through an inlet 60 into the expansion tank 35 near the top of this tank at a level which is above the normal operating liquid level 61 therein.

For heating the passenger compartment 62, there is an electrical heater motor 64 driving a blower wheel 65. The air is drawn in through openings 66 and is impelled by the blower through passageway 67 adjacent to the tank 35. This air becomes heated, and the amount of heated air flowing into the passenger compartment 62 is set by control means, for example such as an adjustable louvre 68, to control the temperature in the passenger compartment as desired. An advantage of this heater apparatus 34 is that the tank 35 is always at substantially the same temperature, the summer or winter, at slow car speed or high car speed, at light or heavy engine loads, being at the boiling temperature of the coolant liquid. A layer of thermal insulation 70 surrounds the unit 34 to conserve heat energy.

At the top of the vapor condenser 50 there is a header chamber 94 connected to the passages 51, and a vacuumcontrolled spring plug 96 (FIGURE 7) serves to prevent loss of coolant when the engine is shut off. This type of valve is also shown in my Patent No. 3,223,075. An air vent line 97 with a one-way valve 98 is connected to the header 94 at a point remote from the condensing surfaces in order to prevent pressure from building up within the cooling system to too high a degree and also to prevent air of the atmosphere from entering the system. In order to reduce to a minimum loss of coolant through the air vent 97 during the momentary rise in pressure in the cooling system due to the latent heat remaining in the system after the engine has been shut down, the valve 98 allows pressure to build up to a low level when the engine is running and to a somewhat increased level when the engine is shut down.

The flexible tubular valve 98 at the end of the line 97 is inserted between two members 99 and 100, the bottom member 100 being stationary and the top member 99 being a plug connected to one side of a spring biased diaphragm 101. On the other side of the diaphragm 101 there is a connection 102 to the vacuum side of the engine manifold so that when the engine is operating the vacuum acts to draw the diaphragm 101 to relieve the pressure exerted against the flexible tubular valve 98, at which time the valve is set for a suitable low pressure, for example of approximately one-half pound per square inch. When the engine stops and the vacuum is cut off, the diaphragm is no longer drawn, and the valve is set for a somewhat increased pressure, for example of approximately two to five pounds per square inch.

It is an advantage of this cooling system as described that it requires less liquid coolant than the system disclosed in my Patent No. 3,223,075 and requires far less liquid coolant than is used in a conventional water-cooled engine of equivalent power and size. For summer driving or in geographic locations Where the Winter temperature remains above freezing, the coolant liquid may be water containing a rust inhibitor. For sub-freezing temperatures a suitable liquid coolant includes water plus Dowtherm 209, having a property of forming an azeotrope with 47 weight percent water, has an atmospheric boiling point of 209 F. Also, mere azeotropic conditions exist with solutions containing from 3060 weight percent of Dowtherm, hence, maintaining exact concentration in the ebullient cooling system is not critical. Weather conditions, likewise, present no problem for Dowtherm pour points range from -l8 F. for a 40 weight percent solution to 80 F. for one of 60 percent.

The coolant liquid, for example water containing rust inhibitor is poured in by removing a liquid-tight filler cap 104 (FIGURES 2 and 4) on a fill pipe 105 connected into the side of the compensating chamber 24 at a level so that no more than the recommended quantity of liquid coolant can be introduced into the system. The cold coolant liquid level is shown at L, and the liquid coolant level in the engine jacket 12 remains below the top of the engine block when the engine is cold and not operating. When the engine is started, the engine pump 11 immediately starts pumping liquid coolant from the compensator cham ber 24 to fill the jacket 12 about the engine block and to introduce liquid up into the head jacket 18, and at the same time it lowers the liquid level Within the compensator chamber 24. Thus, the space gained in the compensator 24 is available to receive the expanded volume of liquid when it reaches the boiling point.

By using the space generally provided for the car heater near the fire wall 106 in the engine section beneath the hood 54 this present system gains more space for separating dry vapor from the wet vapor which rises from the compensator to the expansion tank 35 in the car heater assembly 34. The car heater expansion tank 35 enables a much smaller compensator chamber 24 to be used than heretofore and which may now be located in several different and smaller spaces than the larger compensator shown in my Patent No. 3,223,075. Also, by virtue of the smaller compensator 24 less liquid coolant is enabled to be used to fill the cooling system. This smaller quantity of liquid coolant allows for a faster warm-up from cold, it saves Weight and reduces expense for the operator. For example, a 385 horsepower Oldsmobile Jetstar engine (1965), when operated as a conventional water-cooled engine is intended to utilize approximately 16 quarts,

whereas this same engine when employing the present invention uses approximately 11 quarts.

In operation the level of liquid coolant in the expansion tank 35 varies with the power output of the engine. When the engine is being operated at high power output, greater volumes of vapor are generated, thus displacing more boiling liquid from the jacket and driving more wet vapor up into the expansion tank and raising the level of liquid therein. Conversely, when the engine is being operated at low power output the level of coolant liquid in the expansion tank 35 is lower. The bottom of this tank is positioned above the water line L so that upon shut down of the engine the liquid runs down into the compensating chamber 24. By virtue of this arrangement a relatively small amount of liquid coolant is required as compared with a conventional water cooled engine of equivalent power output.

In the embodiment of the ebullient cooling system as shown in FIGURE 8 parts which perform functions corresponding to those in FIGURES 1-7 have reference numbers corresponding therewith. The high velocity flow 19 of the coolant, both liquid and vapor, passes forward through the head jacket 18 and issues through the outlet 20. From this outlet 20 the mixture of vapor and liquid rushes through suitable connection means 21 in the form of flexible tubing, duct, or hose extending directly from the outlet 20 to an inlet 33 of a tank 35 in the passenger heater 34.

The heater 34 of FIGURE 8 is substantially identical to that shown in FIGURE 6, except that in FIGURE 8 the funnel-shaped return port 38 is enlarged and extends downwardly relatively more than in FIGURE 6. Also, in FIGURE 8 the circuit connections are different from those shown in FIGURES 1-7, as will be explained.

In FIGURE 8, the connection means 39 extends from the return port 38 forward to the inlet to the pump 11. This connection means 39 may be any suitable flexible tubing, duct or hose. The liquid is driven down through the port 38 and through this connection means 39 by the impelling force resulting from the downward rush of liquid and vapor passing down from the inlet 33 through a duct 36 similar to the action illustrated in FIGURE 6. The end of the duct 36 forms a nozzle which is aimed toward and is positioned closely adjacent to the outlet port 38.

In the tank or chamber 35, the vapor is released from the mixture of vapor and liquid issuing from the lower end of the duct 36, and this vapor rises up within the chamber 35 and issues through a top outlet 44 from the chamber 35. From the outlet 44 suitable connection means 45 extends over to a vapor header 94 located along the top of the vapor condenser 50, so that the vapor enters the condenser 50 and flows downwardly through the multiple vertical cooling passages 51 therein. Thus, the vapor becomes condensed and falls into a condensate collector 46 communicating with the lower ends of the condensing passages 51.

From the collector pan 46 the hot condensate liquid flows down through a pipe 56 into condensate pump 58 to be pumped up through tubing 59 and through an inlet 60 into the tank 35. Thus, the condensed liquid is returned into the circulation path so as to reach the cooling jacket of the engine. The inlet 60 is located at a level which is above the normal operating liquid level in the chamber 35 as seen by the broken away section of this chamber.

In order to allow air to escape from the ebullient cooling system during the period after start-up of the engine when the cooling system is coming up to its normal operating temperature, there is a thermostat valve 108 connected to the upper end of a large diameter vent pipe 110. This thermostat valve 108 is located relatively high up under the hood with respect to the condenser 50, and the large diameter vent pipe 110 has a substantial vertical length extending donw near to the collector pan 46 and being connected thereto by a tube 112. As soon as the system has come up to temperature, the coolant vapor, i.e., steam, causes the thermostat 108 to close.

The vent pipe 110 has a relatively large diameter, e.g. 1.5 inches, and thus it provides large flow capacity so that any steam rising therein will not tend to drive coolant liquid, i.e., water, up this vent pipe. That is, the steam can bubble up through any water which happens to be in this pipe.

Also connected to the top of the vent pipe 110 is a spring-loaded pop valve 114 which is set to open at a suitable pressure, for example 3 to 7 pounds per square inch. This pop valve 114 is set at a pressure level which reduces to a small amount the loss of coolant through the valve 114 during the momentary rise in pressure in the cooling system due to the latent heat remaining in the system after the engine has been shut down.

The terms and expressions which I have employed are used in a descriptive and not a limiting sense, and I have no intention of excluding equivalents of the invention described and claimed.

What is claimed is:

1. A constant temperature heater for heating the passenger compartment of an automobile, said heater having its temperature maintained constant by tank means having an inlet adapted to receive a mixture of vapor and coolant liquid at its boiling point, an outlet in the lower portion of said tank means for passing coolant liquid, an outlet at the upper portion of said tank means for passing vapor, an electric motor driven blower, a passageway connected to receive air from the blower, said passageway being in heat exchange relationship with said tank means for heating the air passing through said passageway, and means for regulating the flow of the heated air to the passenger compartment.

2. A constant temperature heater for heating the passenger compartment of an automobile as claimed in claim 1 in which said outlet in the lower portion of said tank means extends downwardly and said inlet includes a duct extending into said tank means and being aimed toward said outlet for propelling liquid coolant downwardly out of said tank means through said outlet.

3. A constant temperature heater for heating the passenger compartment of an automobile as claimed in claim 2 in which said outlet is funnel shaped converging downwardly, said outlet being positioned at a level approximating the initial level L of the coolant liquid in the cooling jacket of the automobile engine when at ambient temperature prior to start up of the engine.

4. An ebullient cooling system for an automotive in ternal combustion engine of the reciprocating type having a cooling jacket adapted for a coolant to 'be circulated therethrough with a jacket inlet and a jacket outlet and a coolant circulating pump communicating with said jacket inlet, said cooling system comprising a heater for heating the passenger compartment of an automobile including tank means defining a chamber, said chamber having a first outlet in the lower portion thereof and a second outlet in the upper portion thereof and an inlet duct aimed toward said first outlet, said inlet duct communicating with said chamber, said system circulating coolant vapor mixed with liquid coolant from said jacket outlet to said inlet duct for propelling coolant liquid from said chamber out through said first outlet and allowing the release of vapor into said chamber, said system circulating coolant liquid from said first outlet to said jacket inlet, said system including a condenser having a header at the upper portion thereof and a collector for condensate at the lower portion thereof with a multiplicity of condensing passages extending between said header and said collector, connection means extending from said second outlet to said condenser header for supplying vapor from said heater chamber to said condenser, and condensate return pumping means connected to said collector for returning the condensate to said engine cooling jacket.

5. An ebullient cooling system for an automotive internal combustion engine of the reciprocating type as claimed in claim 4 including a large diameter vent pipe connected at its lower end to the lower portion of said condenser, said vent pipe extending upwardly, a normally open thermostat valve connected to the upper end of said vent pipe, and a normally closed spring-loaded pop valve connected to the upper end of said vent pipe.

6. An ebullient cooling system for an automotive internal combustion engine of the reciprocating type as claimed in claim 4 in which said heater includes an electric motor driven blower, a passageway connected to receive air from the blower, said passageway being in heat exchange relationship with said tank means for heating the air passing through said passageway, and control means for regulating the flow of the heated air to the passenger compartment.

References Cited UNITED STATES PATENTS Weinberg 123-1 Schwartz 12375 X Price 123-179 Aspin 123-10 X Hanlon 123--180 Ostling 123--117 Barber 123-32 Houdry 123-1 Barlow 12341.24

15 EDWARD J. MICHAEL, Primary Examiner. 

